The invention is particularly well suited for use with tires for trucks, earthmovers, or military vehicles which operate off-the-road, and especially those tires which employ a removable tread, or a detachable traction band with metallic grouser bars as shown and described in U.S. Pat. No. 3,871,720. The sidewalls of such tires are vulnerable to punctures from sharply pointed rocks and pieces of metal, and other jagged material which the tire is likely to encounter as it rolls over the rough terrain on which off-the-road type vehicles are designed to operate. Passenger tires of the early nineteen hundreds were also highly susceptible to punctures. Consequently, there has been a continuing effort to find some way of protecting the protruding, flexed sidewalls of a tire without detracting from the design characteristics of the tire.
Curved, metal protector plates, as shown and described in U.S. Pat. No. 1,266,403, have been used with little success to shield the vulnerable sidewalls of the tire. Non-metallic shields, such as those shown and described in U.S. Pat. Nos. 820,296 and 1,450,800, were also used to protect the sidewalls. The 1,450,800 patent is especially interesting because it discloses the use of rubber sidewall stock only in the upper sidewall areas of the tire, rather than extending the sidewall rubber completely around the entire tire carcass into the bead areas of the tire. In both cases, the protecting shields adversely affect the operational characteristics of the tire, since the shields are permanently adhered to the tire and will, therefore, experience the tension and bending stresses of the tire, which stresses act to enlarge cuts or snags that occur in the sidewalls of the tire. The invention is directed to a simple, economical method of protecting the sidewalls without interfering with the design characteristics of the tire.
Briefly stated, the invention is in the provision of resilient, annular shields for protecting the sidewalls of a tire. The shields are each composed of a suitable resilient material, e.g. rubber, and are positioned for absorbing the cuts and bruises normally inflicted on the sidewalls of the tire. The annular shields are attached to the tire such that portions of the shields covering the sidewalls are free of the sidewalls so that the stresses experienced by the sidewalls as they flex during operation of the tire, will not be imparted to the shields.
Thus, unlike a cut in the sidewall of the tire, a cut in a shield will not grow or become enlarged during flexing or deflection of the tire. The shields are demountable from the tire such that a highly abused and worn shield may be removed and replaced with a new shield to prolong the life of the tire.